Ups, sorry, I did one mistake, I forgot we are filtering incoming traffic and the we need to match destination ip. Also there is no need to filter the hole subnet, so we can set the mask to 32. So this would be the result:
<br><br><span style="font-family: courier new,monospace;">
########## downlink #############</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;"># slow downloads down to somewhat less than the real speed to prevent </span><br style="font-family: courier new,monospace;">
<span style="font-family: courier new,monospace;"># queuing at our ISP. Tune to see how high you can set it.</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;"># ISPs tend to have *huge* queues to make sure big downloads are fast
</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">#</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;"># attach ingress policer:
</span><br style="font-family: courier new,monospace;"><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">tc qdisc add dev $DEV handle ffff: ingress</span><br style="font-family: courier new,monospace;">
<br>HERE BEGINS THE CHANGE<br><span style="font-family: courier new,monospace;"># filter for your roomate, drop everything that's</span><br style="font-family: courier new,monospace;">
<span style="font-family: courier new,monospace;"># coming faster than half the DOWNLINK value:</span><br style="font-family: courier new,monospace;">
<br style="font-family: courier new,monospace;">
<span style="font-family: courier new,monospace;">tc filter add dev $DEV parent ffff: protocol ip prio 50 u32 match ip dst \</span><br style="font-family: courier new,monospace;">
<span style="font-family: courier new,monospace;"> <a href="http://192.168.10.3/24" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">192.168.10.3/32</a> police rate $[$DOWNLINK/2]kbit burst 10k drop flowid :1
</span><br style="font-family: courier new,monospace;">
HERE ENDS THE CHANGE<br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;"><br># filter *everything* to it (<a href="http://0.0.0.0/0" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">
0.0.0.0/0</a>), drop everything that's
</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;"># coming in too fast:</span><br style="font-family: courier new,monospace;"><br style="font-family: courier new,monospace;">
<span style="font-family: courier new,monospace;">tc filter add dev $DEV parent ffff: protocol ip prio 50 u32 match ip src \</span><br style="font-family: courier new,monospace;"><span style="font-family: courier new,monospace;">
<a href="http://0.0.0.0/0" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">0.0.0.0/0</a> police rate ${DOWNLINK}kbit burst 10k drop flowid :1</span><br style="font-family: courier new,monospace;">
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